bump stb
bump stb

* stb 8428bcf...ccdebab (14):
  > 64-bit compilation fix for stb__try_chunk
  > Use stb_uinta for pointer-sized unsigned int
  > version number
  > Merge branch 'master' of https://github.com/Sofahamster/stb into working Fix missing types to be 'unsigned char' not 'int' Fix handling of string constants which are const-char-* on modern compilers
  > add missing types to allow compiling as C++, and use less cache
  > disambiguate
  > Merge branch 'master' of https://github.com/nothings/stb
  > voxel render 0.78; compile as C++, fix bad #else
  > stb_voxel_render version 0.77
  > rename static-implementation define to STB_VOXEL_RENDER_STATIC for consistency
  > Merge branch 'master' into working
  < 64-bit compilation fix for stb__try_chunk
  < Use stb_uinta for pointer-sized unsigned int
  > quick fixes w/o version updates

krig/roam,krig/roam